The extraction process for green radish polysaccharide (GRP) was optimized to improve the extraction yield of GRP by varying the enzyme activity, enzymatic hydrolysis time and temperature, and solid-solvent ratio in singlefactor experiments using response surface methodology. The optimal GRP extraction process involved an enzyme activity of 285 U/g, an enzymatic hydrolysis temperature of 48 ℃, an enzymatic hydrolysis time of 59 min, and a solid-solvent ratio of 1:21. The average yield of GRP extracted using this process was 5.34%. GRP was composed primarily of ten monosaccharides with a molar ratio of mannose: ribose: rhamnose: glucuronic acid: galacturonic acid: glucose: galactose: xylose: arabinose: fuc ose = 0.827: 0.365: 1.216: 1.519: 2.853: 66.215: 17.425: 0.295: 8.713: 0.574. Additionally, GRP presented excellent antioxidant capacity, and its scavenging rates for 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonate) radical, hydroxyl radical, and 1,1-diphenyl-2-trinitrophenylhydrazine radical were 91.14%, 85.31%, and 62.73%, respectively, with half-maximal inhibitory concentrations of 10.78, 8.42, and 17.40 mg/mL, respectively. The optimal GRP extraction process, monosaccharide composition and structure of GPR, and excellent antioxidant activity of GPR were determined, providing a reference for further research on the physiological activity of GRP and development of relevant health food.